Vehicle

ABSTRACT

A vehicle, either powered or a trailer (1), having a yoke or U-shaped chassis (2) and a drop tray (3) with a tailgate (4) at the rear of the chassis (2) either hinged to the sidewall (6) or to the drop tray decking (5). The tray (3) has parallel posts (13) extending in a general upward direction while the chassis (2) has hollow tubes (12), which mate with the parallel posts (13). Any suitable lifting mechanism could be employed, however hydraulic cylinders (21) are preferable located at each corner of the chassis (2), to operate simultaneously to raise and lower the tray (3) such that it maintains substantially the same orientation throughout its movement between its transport position, above the ground, and its loading position, in which the tray (3) engages the ground.

BACKGROUND OF THE INVENTION

The present invention relates to vehicles either non powered such astrailers or powered such as pick up trucks, trucks and vans, having avertically adjustable bed.

Standard vehicles such as vans and trucks have been used for thetransportation of cargo. However, because of the height of the tray orbed above the ground, loading, unloading and positioning of cargo can bedifficult.

In practice, devices such as fork lifts, lifting tailgates and ramps areused. These however have their disadvantages such as costs andavailability at any particular site.

Attempts to overcome the above disadvantages have been made utilizingeither pivoting trays or adjustable trays in which parallelogramlinkages are employed.

With the pivoting type trays such as is shown in U.S. Pat. No.5,288,197, the back end of the tray is pivoted to the ground, forming aramp up which the load is driven, in the case of vehicles, or pushed.This method of loading is not always convenient due to the problems ofthe loading onto an inclined ramp.

Adjustable trays have been proposed as shown in Australian Patent 573414 and Australian Patent Application No. 70142/91. In both of thesespecifications, parallelogram linkages in the form of "dog lcg" or"boomerang" linkages are used, with the power means or rams acting onthe linkages normal to the displacement of the tray. Further in both ofthese specifications the tray swings to a position rearway of the backof the vehicle, which could present problems in use. In U.S. Pat. No.4,673,328 again a parallelogram type linkage is used having fourpivotable tracks.

The construction shown in Australian Patent Application No. 70142/91utilizes a complicated chassis construction with a torque box, rolloverbar and support bars required to give stability to the yoke shapedchassis.

SUMMARY OF THE INVENTION

The present invention seeks to ameliorate the disadvantages of the priorart by providing a vehicle comprising

a tray having posts parallel to each other extending from the tray;

a yoke or U-shaped chassis having side wall extending substantiallynormal to the plane of the chassis;

parallel elongated members located in such side walls;

drive means to move said bed between a transport position and a loadingposition such that said tray retains substantially the same orientationthroughout its movement between said transportation position and saidloading position, with said elongated members being telescopicallyengaged with respective posts of the tray.

Preferably the elongated members and said posts are respectively normalto said yoke shaped chassis and said tray.

In another broad form the invention comprises a wheel assembly adaptedfor connection to a chassis comprising:

a first trailing arm pivotally suspended from a first end to thechassis;

a first wheel mounting stub axle located at or adjacent the free end ofthe first trailing arm;

a first connection means located adjacent said first wheel mounting stubaxle;

a second trailing arm pivotally suspended, from a first end, to thechassis and angled with respect to the chassis in the direction as thefirst trailing arm;

a second wheel mounting stub axle located at or adjacent the free end ofthe second trailing arm;

a second connection means located adjacent said second wheel mountingstub axle;

a first bracket located on the chassis intermediate the said first andsecond training arms;

a second bracket located on the chassis on one side of the first bracketbeyond said first wheel mounting stub axle;

a third bracket located on the other side of said first bracket beyondsaid second wheel mounting stub axle;

a pivoting linkage connected to said first bracket and extending on eachside thereof;

a first leaf spring connected between one end of said pivoting linkageand said second bracket with said first connection means from said firstconnection means from asid first trailing arm connected to the middle ofsaid first leaf spring; and

a second leaf spring connected between the outer end of said pivotinglinkage and said third bracket, with said second connection meansconnected to the middle of said second leaf spring.

In a further form the invention comprises a hydraulic control mechanismfor a vehicle which has a yoke or U-shaped chassis, with a tray moveablysupported thereon, which tray is moveable between a transport positionand a loading position, with the tray remaining substantially horizontalduring movement, comprising:

four hydraulic cylinders located adjacent the corners of the vehiclechassis to raise and lower the tray between the transport and theloading positions;

a hydraulic motor;

a hydraulic fluid sump;

a spool valve;

a first fluid line connected from said sump via said motor to said spoolvalve;

a second fluid line connected from said spool valve to said sump;

a third fluid line connected from said spool valve to a first flowdivider/combiner which passes fluid through a first outlet to a secondflow divider/combiner, and through a second outlet to a third flowdivider/combiner, wherein each outlet of the second and third flowdividers/combiners is connected to one side of a respective one of saidfour hydraulic cylinders;

a fourth flow divider/combiner having a first and a second inlet, and anoutlet;

a fifth flow divider/combiner having a first and second inlet and anoutlet, with each inlet of said fourth and fifth flow dividers/combinersbeing connected to the other side of one of the respective cylinders;

a sixth flow divider/combiner having two inlets and an outlet, with itsinlets each being connected to a respective outlet of said fourth andsaid fifth flow dividers/combiners, and its outlet being connected tosaid spool valve,

wherein said spool valve has a first position to allow fluid to flow ina first direction through the said flow dividers/combiners to move thepistons simultaneously to lower the tray, and second position to allowfluid to flow in a second direction through the said flowdividers/combiners to move the pistons simultaneously to raise the tray.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described with reference to the accompanyingdrawings in which:

FIG. 1 illustrates a rear view of a trailer with the bed in a loadingposition made in accordance with an embodiment of the present invention;

FIG. 2 illustrates another rear view of the trailer shown in FIG. 1 withthe bed in the transport position;

FIG. 3 illustrates a view of the chassis shown in FIGS. 1 and 2;

FIG. 4 illustrates a view of the tray shown in FIGS. 1 and 2;

FIG. 5 illustrates a schematic rear view of a tray shown in FIG. 4 inits transport position;

FIG. 6 illustrates a schematic rear view of the tray illustrated in FIG.4 in its loading position;

FIG. 7 illustrates a detailed view of the chassis of FIGS. 1 and 2,showing the wheel suspension assembly;

FIG. 8 illustrates a side view of the wheel suspension assembly of FIG.7.

FIG. 9 illustrates the front view of the tray illustrated in FIG. 4;

FIG. 10 illustrates the hydraulic system according to the one embodimentof the present invention;

FIG. 11 illustrates the electrical system according to one embodiment ofthe present invention;

FIGS. 12 to 15 illustrate various configurations of trailers made inaccordance with embodiments of the present invention; and

FIG. 16 illustrates another embodiment of the trailing arm andsuspension system.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

A trailer is shown schematically in FIGS. 1 and 2 embodying the presentinvention. The trailer (1) comprises a yoke-shaped chassis (2) and adrop tray (3). A tailgate (4) is located at the rear of the trailer (1);the tailgate (4) being hingedly connected to the side wall (6) or to thedrop tray decking (5).

Thus in use the tailgate is unlatched and can be either swung to theside or dropped or lifted out, and then the drop tray (3) is lowered ordropped to the ground. However, as shown in FIGS. 1 and 2 the tailgate(4) is hingedly connected to the tray floor (5).

The chassis (2) as shown FIGS. 1, 2 & 3 comprises two top rails (7)joined by a top end rail (8). Reinforcing struts (9) link the top rails(7) and (8) to identical bottom side rails (10) and bottom end rails(11) respectively. Located at each corner of the chassis (2) are hollowtubes (12) which are adapted to telescopically mate with the uprightpost (13) of the tray (3). Suitable cladding (not shown) is placed onthe outer surface forming a stable side wall.

A drop tray (3) is constructed as shown in FIGS. 4 & 9, having two sidemembers (14) joined by traversemembers (not shown), with a decking (5)secured across on top. Upright posts (13) extend normal to the plane ofthe drop tray decking (5). A sheet (16) is connected normal to thedecing (5) a distance away from the posts (13).

As shown in FIG. 9 gussets (17) are connected across the last twotraverse members (18) and the back plate (19).

The posts (13), in use, engage telescopically with the hollow tubes (12)as shown in FIG. 1, 5 & 6. The side sheet (16) as shown in FIG. 4 hasnylon strips (20) located thereon to act as a bearing strip against thehollow tube (12).

As can be seen from this embodiment there is a hollow side tube (12)located on each corner of the yoke shaped chassis (2). In each of thesetubes (12), a post (13) engages. This engagement enhances the rigidityof the vehicle.

To operate the tray (3), from its transport position to its groundengaging loading position, any suitable lifting means could be used suchas motor driven thread and fixed nut arrangements, or cables. However,preferably as shown in FIGS. 1 and 2, hydraulic cylinders (21) areconnected to the side rail (7) and have their cylinder rod (22) passingthrough the bottom side rail (10) to engage with the side member (14) ofthe tray (2) at connection (23). A hydraulic cylinder (21) is locatedadjacent the four corners of the frame.

Thus to raise or lower the drop tray (2) the cylinders are activatedsimultaneously raising and lowering the tray (2) parallel to the planeof the chassis.

It is not necessary that the posts (13) and hollow tubes (12) be normalto the frame, as they could be at any suitable angle such as 45° to movethe tray (2) rearward of the vehicle.

Further the male post could be on the chassis with the female hollowmembers on the tray.

An operating system will be described subsequently.

An improved suspension/wheel mounting system has been developed, anembodiment of which is shown in FIGS. 1, 2, 3, 7 and 8.

This system utilizes two wheels (24) and (25) on each side of thechassis (2). Each wheel (24) and (25) is connected to a stub axle (26)and (27) respectively, extending from a trailing arm (28) and (29) whichare pivotally connected to a support rail (15) attached to the bottomrail (10). Extending opposite the stub axles (26) and (27) at the freeends of the trailing arms (28) and (29) are projections (30) and (31).These projections are pivotally secured by any suitable means such asU-bolts (32) backing plate (33) and nuts (34) to the respective leafsprings (35).

Located intermediate the trailing arms (28) and (29) is a bracket (36)connected to the support rail (15). A first linkage (37) is pivotallyconnected intermediate its ends to the bracket (36). A first end (38) ispivotally connected to one end of the leaf spring (35), while the otherend of the leaf spring (35) is connected by a pivotal linkage (39) tothe support rail (15).

The second leaf spring (40) is pivotally connected at one end to thesupport rail (15) and connected at the other end by pivotal linkage (41)to the second end (42) of the first linkage (37).

To transfer weight back to the chassis (2) a support plate (43) isprovided as particularly shown in FIGS. 7 and 8. The trailing arms (28)and (29) are mounted on a respective projection (44) with a bush andspacer (not shown). The support plate (43) has located at one endtubular section (47) which fits over the free end of the projection(44), with the cut out (48) accommodating the trailing arm (28), asshown in FIG. 7. The edge (49) of the support plate (43) is welded tothe reinforcing struts (9), thus securing the trailing arm (28) andtransferring the load back to the chassis (2).

A modified suspension system is shown in FIG. 16 wherein a detailed viewof the suspension connection to the trailing arm is shown.

The arrangement of the wheel suspension is as described previously,except that the leaf spring (35) are at their centers supported by aspring holder (95), which is supported on a bearing (97) to the member(96) which is secured to the trailing arm (28).

The tailgate (4) is raised and lowered by the tailgate cylinder (50)which is connected to the tray (3) by connection (51) and to the linkage(52) on the tail gate (4) as shown in FIG. 1.

FIG. 10 is a schematic of the hydraulic system of one embodiment of thepresent invention. A hydraulic motor (53) draws fluid from the sump (54)and pumps it to a solenoid spool valve (55). In a first position thespool valve (55) passes fluid through to a first flow divider/combiner(56) such as those sold under the trade mark Hydraform, which has twooutlets dividing the flow to two further flow dividers/combiners (57)and (58). The flow dividers/combiners being set to equally distributethe flow. The output of each of the flow dividers/combiners (57) and(58) communicates with the power side or extension side of a respectivetray operating cylinder (59, 60, 61 and 62), with the return side orretraction side of the cylinders being connected to respective inputs offlow divider/combiners (63) to (64), the outputs of which are combinedthrough the flow divider/combiner (65) and back into the sump (54). Thespool valve (55) has a second position wherein the flow is reversedthrough the flow dividers and the pistons are retracted.

Pilot check valves (66, 67, 68 and 69) can be connected directly to thecylinders (59, 60, 61 and 62) as shown or a single pilot check valve(not shown) can be connected between the flow dividers (56 and 57) andthe spool valve (55).

To operate the tailgate cylinder (50) an additional spool valve (70) isconnected via the spool valve (55) to the hydraulic motor drive fluid,to open or close the tailgate depending on the position of the spoolvalve (70).

Shown in FIG. 11 is the electrical schematic circuitry. As can be seenthe trailer is self powered having its own battery. The circuitryprovides a provision for direct charging of the trailer battery (82)from the car to which it is connected.

The floor down solenoid (84), floor up solenoid (85), tailgate downsolenoid (86), and tailgate up solenoid (83) are connected via therespective floor down relay (87), floor up relay (88), tailgate downrelay (89) and tailgate up relay (90) to the hydraulic valves (91)located next to the hydraulic motor (92).

The wheels each have an electric brake (93) operated by the electricbrake relay (94).

Separate looking mechanisms are provided to lock the tray in itstransport position. This can utilize any suitable arrangement coupledwith a fail safe system to prevent operation of the tray if the tray isstill locked to the chassis.

Further, in the line to the tailgate cylinder, is a pressure sensitivevalve whereby if an object is blocking the closing of the tailgate theincrease in resistance to the movement of the ram is detected and theram is disabled until the object is removed.

The basis chassis construction can be used with many different bodypanel designs. One embodiment is shown in FIG. 12 in which storage units(71) are rigidly connected to the chassis (2) and the support plates(43), to provide additional rigidity of the chassis (2).

The trailer (1) as shown in FIG. 12 can be mofified to include a canopy(72) covering a framework (73) as shown in FIG. 14, or a carrying rack(74) as shown in FIG. 13.

The basic trailer chassis can be modified to produce a horse float (75)as shown in FIG. 15. The operation of the tray is identical to thepreviously described operation, and the trailer chassis and wheelsuspension systems are substantially identical to these describedpreviously.

The addition of the roof bracking (76) and the storage units (77) whichare also connected to the support plates (43) resist any twisting of thehorse float (75). The horse float body has a back entrance door (78) anda front door (79).

The tray is divided into two stalls with appropriate horse padding onthe divider and side walls (81). Each stall has its own rear door (80).

It should be obvious that modifications and alterations could be made tothe above described invention without departing from the scope or spiritof the present invention.

I claim:
 1. A vehicle comprising:a U-shaped chassis formed by: a toprail having two substantially parallel arm members and a base memberlinking said arm members; a bottom rail substantially overlaid by saidtop rail, and having two substantally parallel arm members and a basemember linking said arm members; and a plurality of elongated hollow,substantially parallel members rigidly joining said top and bottomrails; a tray having a plurality of posts parallel to each otherextending from the tray; each of said posts mating in sliding engagementwithin a respective elongated hollow substantially parallel member, soas to enhance the rigidity of the chassis; a wheel assembly locatedintermediate the ends of each arm member of said bottom rail; and drivemeans to move said tray between a raised transport position and a groundengaging loading position such that said tray retains substantially thesame orientation throughout its movement between said transport positionand said loading position, as a result of the sliding engagement of thesaid posts within the respective elongated hollow substantially parallelmembers.
 2. A vehicle according to claim 1, wherein there is one of saidposts and a respective one of said elongated members located adjacent arespective corner of the U-shaped chassis.
 3. A vehicle according toclaim 2 wherein the drive means comprises four units, each locatedadjacent a respective corner of the U-shaped chassis, and having amoving component passing through the respective bottom rails of thechassis to connect to the tray.
 4. A vehicle according to claim 2,wherein the drive means comprises four hydraulic cylinders, each locatedadjacent a respective corner of the U-shaped chassis, and having itscylinder rod passing through the respective bottom rails of the chassisto connect to the tray.
 5. A vehicle according to claim 4, wherein eachwheel assembly comprises:a first trailing arm, having first and secondends, pivotally suspended at said first end from the chassis and havingsaid second end free, and angled with respect to the chassis; a firstwheel mounting stub axle located at or adjacent the free end of thetrailing arm; a first connection means located adjacent said first wheelmounting stub axle; a second trailing arm, having first and second ends,pivotally suspended at said first end from the chassis and having saidsecond end free, and angled with respect to the chassis in the samedirection as the first trailing arm; a second wheel mounting stub axlelocated at or adjacent the free end of the second trailing arm; a secondconnection means located adjacent said second wheel mounting stub axle;a first bracket located on the chassis intermediate the said first andsecond trailing arms; a second bracket located on the chassis on the oneside of said first bracket beyond said first wheel mounting stub axle; athird bracket located on the chassis on the other side of said firstbracket beyond said second wheel mounting stub axle; a pivoting linkageconnected to said first bracket and extending on each side thereof; afirst leaf spring connected between one end of said pivoting linkage andsaid second bracket with said first connection means of said firsttrailing arm connected to the middle of said first leaf spring; and asecond leaf spring connected between the other end of said pivotinglinkage and said third bracket, with said second connection means ofsaid second trailing arm connected to the middle of said second leafspring.
 6. A vehicle according to claim 5, wherein each trailing arm ispivoted on a shaft having a free end engaged by a support plate which isfixed attached to a reinforcing strut of the chassis.
 7. A vehicleaccording to claim 6, wherein storage units are rigidly attached to theside walls of the chassis and to the support plates.
 8. A vehicleaccording to claim 5, wherein said first connection means is pivotallyconnected to a fourth bracket which is connected to the middle of thesaid first leaf spring and said second connection means is pivotallyconnected to a fifth bracket which is connected to the middle of thesaid second leaf spring.
 9. A vehicle according to claim 8, wherein eachtrailing arm is pivoted on a shaft having a free end engaged by asupport plate which is fixedly attached to a reinforcing strut of thechassis.
 10. A vehicle according to claim 9, wherein storage units arerigidly attached to the side walls of the chassis and to the supportplates.
 11. A vehicle comprising:a U-shaped chassis formed by:a top railhaving two substantially parallel arm members and a base member linkingsaid arm members; a bottom rail substantially overlaid by said top rail,and having two substantially parallel arm members and a base memberlinking said arm members; and a plurality of elongated hollow,substantially parallel members rigidly joining said top and bottom railsand extending substantially normal to the plane of the chassis; a trayhaving a plurality of posts parallel to each other extending from thetray; each of said posts mating in sliding engagement within arespective elongated hollow substantially parallel members, so as toenhance the rigidity of the chassis; a wheel assembly locatedintermediate the ends of each arm member of said bottom rail; and drivemeans to move said tray between a raised transport position and a groundengaging loading position such that said tray retains substantially thesame orientation throughout its movement between said transport positionand said loading position, as a result of the sliding engagement of thesaid posts within the respective elongated hollow substantially parallelmembers.
 12. A vehicle according to claim 11, wherein there is one ofsaid posts and a respective one of said elongated members locatedadjacent a respective corner of the U-shaped chassis.
 13. A vehicleaccording to claim 12, wherein the drive means comprises four hydrauliccylinders, each located adjacent a respective corner of the U-shapedchassis, and having its cylinder rod passing through the respectivebottom rails of the chassis to connect to the tray.
 14. A vehicleaccording to claim 13, wherein each wheel assembly comprises:a firsttrailing arm, having first and second ends, pivotally suspended at saidfirst end from the chassis and having the second end free, and angledwith respect to the chassis; a first wheel mounting stub axle located ator adjacent the free end of the trailing arm; a first connection meanslocated adjacent said first wheel mounting stub axle; a second trailingarm, having first and second ends, pivotally suspended at said first endfrom the chassis and having said second end free, and angled withrespect to the chassis in the same direction as the first trailing arm;a second wheel mounting stub axle located at or adjacent the free end ofthe second trailing arm; a second connection means located adjacent saidsecond wheel mounting stub axle; a first bracket located on the chassisintermediate the said first and second trailing arms; a second bracketlocated on the chassis on the one side of said first bracket beyond saidfirst wheel mounting stub axle; a third bracket located on the chassison the other side of said first bracket beyond said second wheelmounting stub axle; a pivoting linkage connected tos aid first bracketand extending on each side thereof; a first leaf spring connectedbetween one end of said pivoting linkage and said second bracket withsaid first connection means of said first tailing arm connected to themiddle of said first leaf spring; and a second leaf spring connectedbetween the other end of said pivoting linkage and said third bracket,with said second connection means of said second trailing arm connectedto the middle of said second leaf spring.
 15. A vehicle according toclaim 14, wherein each trailing arm is pivoted on a shaft having a freeend engaged by a support plate which is fixedly attached to areinforcing strut of the chassis.
 16. A vehicle according to claim 15,wherein storage units are rigidly attached to the side walls of thechassis and to the support plate.
 17. A vehicle according to claim 14,wherein said first connection means is pivotally connected to a fourthbracket which is connected to the middle of the said first leaf springand said second connection means is pivotally connected to a fifthbracket which is connected to the middle of the said second leaf spring.18. A vehicle according to claim 17, wherein each trailing arm ispivoted on a shaft having a free-end engaged by a support plate which isfixedly attached to a reinforcing strut of the chassis.
 19. A vehicleaccording to claim 18, wherein storage units are rigidly attached to theside walls of the chassis and to the support plates.